he telling the truth nul and kurth do attack sometime even if the disorientation works the attack he uses is unworthy or something he does attack himself and him team but does alot of dmg to us also higher levels might not happen to hav any problem with him but i am lvl 150 and cant afford iso or skins (trying to get 27/30 heroes for the 12.2 mission) and stealthy items dont hav much affect against him so do u hav any low level plan for it ? really need to not get killed (sometimes 1shot kills my agent)
His Unworthy pre-counter is a buff, he loses that ability if you can either stop him from buffing himself (depower) or with buff removal effects, like Scroll of Angolob, Cube, and attacks that apply Soulfire.
SoA can be farmed in incursions, and many heroes and weapons can apply Soulfire, although he might of course pre-counter the attack and kill you.
Cpt. America's Steve Rogers alt with his e-iso that makes him go first in combat is also an option if you can get ahold of those. Use him to depower Nul before he takes a turn. Though without pestilence beast it won't help much if the enemy has mystic.
Alternatively you may have to wait for the next big patch, Nul's pre-counters will be fixed and work the way it's supposed to (it's bugged right now, he's not meant to pre-counter everything)
And, again, kitting up a Phased team is an option, although a bit wonky one. If you can stay phased, Nul can't hit you. Someone like Kitty Shadowcat can even attack with her L9 and remain phased, Nul can't do shit against her until her phase runs out. Dr. Strange's new a-iso can even phase your whole team, and I think his shield has no cooldown so you could potentially spam it every round, and Nul can't stop him since he will be phased while applying a new phase.
Keep yourself phased and just recharge until he smahes his own brains in. And hope the agen't doesn't have cube or SoA (which they all do... 
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